Method and device for lapping gauges



May; 25 1926. 1,586,238

' E. BUCKINGHAM METHOD AND DEVICE FOR LAPPING GAUGES Filed. March 1-9,1924 (Saab III 11m I TTOIMEY Patented May 25, 1926 UNITED STATES earuroiFFicE.

EARLE RUCRINGRAM; or nARTFoRn, CONNECTICUT, ASSIGNOR To PRATT & WHIT-NEY COMBA'NY, OF NEW YORK, n. Y., A coRroRATioN or new JER$EY.

METHOD AND DEVICE FQR LAFPING GAUGES.

Application filed March 19, 1924. Serial No. 700,299.

This invention relates to methods and deoperation serving to bring thegauging surfaces down to. their proper dimensions and shape and topolish the same to a smooth finish. The primary object of the presentinvention is to provide an improved method and device for performingthis lapping op eration on internal taper gauges.

Another object ofthe invention is to provide an improved method anddevice for lappim internal taper thread gauges, such met ed and devicecomprising the support-c ing of a plurality of toothed lapping mem-'bers in a conical relationship and in threaded engagement with the gaugethreads to be lapped, the arrangement of the parts being such that as arelative rotation is ct. fected between the gauge and the lappingniembere suchparts, because of their threaded engagement, also partakeof a relative axial or longitudinal movement while the lapping membersmaintain their conical relationship and their threaded lapping enagementwith the gauge.

\Vith the above and other objects in view, my invention consists in thefeatures of construction and operation set forth in the, followingspecification and illustrated in the accompanying drawing. In suchdrawing annexed hereto and forminga part of this specification, haveshown one en'ibodiment of my invention in connection with a device forlapping internal taper thread gauges but it will be understood that theinvention can be otherwise embodied and that the drawing is not to beconstrued as defining or limit ing the scope of the invention, theclaims appended. to this specification being relied upon for thatpurpose.

Referring to the figures 0t the drawing:

'Figure 1 is a fragmentary perspective view of a lathe showing aninternal taper thread gauge being lapped thereon by my improved lappingdevice.

Fig. 2 is an enlarged side elevation thereof partially in section andbroken away.

Sis a fragmentary perspective view member, the

of the guideway supporting.member for the gauge lapping members.

Fig. l is arraginentary view oi l one of the lapping members.

. Fig. 5 is a crosseection thereof on line 54-5 of Fig. 4.

Fig. 6 is anend view of the member for supporting one end of each of thelapping members. i p v Fig. 7 isan end view ofthe membershown in Fig. 3.

internal cylindrical gauges, both of the plain'and tl readed'type, canbe lapped to an accurate and smooth finish without ditiiculty since the.lap used inthis operation is of the same diameter throughout its lengthand can therefore accomplish the lapping operation merely rotating andreciprocating the same through the gauge; Internal taper gauges howevercannot be lapped in this manner and the lapping of such gauges isperformed, with considerable difficulty.

In my present invention, plurality of lapping members in conicallyarranged guideways in a central supporting said conical. arrangement ofthe guideways corresponding to the taper oi the gauge'to be lapped. Thegauge is mounted in lapping contact with these members and in thelapping operation the members are moved longitudinally along theirguideways and through the gauge, first in one direction and then int-heopposite direction. Since the conical arrangement of the guidewayscorresponds to the taper'ot the gauge, the lapping members maintaintheir original position in lapping contact with the conical or tapergaugingsurface of the gauge throughout the longitudinal movement of themembers. In the accom 'ianying drawing, 1 have illustrated my inventionin connection .with the lapping of a thread gauge but it will beunderstood that the invention broadly contemplates the lapping of anygauge of the internal taper type.

"In the drawing, 1 indicates the headstock center and 2 thetailstockce'nter ot a lathe on which is mounted the supporting arbor 3 of myimprovedlapping device. Supported on the'arbor and preferably integral Islidably mount a I her 6 therein. Guiding plates 3, also preferablsecured to the sides of each member 6, are adapted to slide in slots 8out in the member 6 adjacent and parallel with the ad jacent guideways5.

face of each lapping member are adaptee to engage the threads of thegauge to be lapped.

The lapping members 6 are also preferably engaged at one end by a member10 slidably mounted on one end of the arbor The flange por ion of thismember is slotted at 11 to receive therein the slotted heads 12 of thelapping members, the cooperating slots being so formed that the membersare free to move radially in thefiange. A hand wheel 13 is secured tothe outer-end of the arbor adjacent the member 10.

The thread gauge 14 to be lapped is mounted on the lapping members withthe gauging threads 1% thereof in threaded contact with the teeth 9.lVhen-assembled for the lapping operation, as shown in Fig. 1, the gaugeis seated on a. member 15 secured to the face plate 16 of the lathe bymeans ofclamps 17. The'gauge is held down firmly on the member 15 bymeans of clamping members 18, the ends of which seat in holes in thegauge. By tightening the nuts 19, the gauge is forced tightly againstthe member 15. j

The headstock center 1 is freely slidable in a supporting sleeve 20 andcan be adjusted axially therein by means of a nut 21 threaded to thecenter. Holes 22 are provided in the periphery of this nut and the nutcan he Irotatably adjusted by inserting a rod through diametricallyopposite openings 23 in'the member 12 and into these holes.

As illustrated in Fig. 2, the conical arrangement of the guideways 5corresponds to the taper of the gauge to be lapped. Gauges varying insize but-corresponding in taper can be lapped with the same lappingdevice by adjusting the member 4c axially to bring the lapping membersinto accurate lapping contact with the gauge. Axial adjustment of themember to the left (Fig. 2) expands the lapping members and adjustmentthereof to the right retracts such members. This adjustment is made byrotating the nut 21, the tailstock center 2 of course being adjusted inlike manner whereby to properly engage and support the arbor- In thelapping operation the parts are assembled in the manner illustrated anddescribed. Before beginning the lapping. movement, the nut 21 isaccurately adjusted to bring the lapping members into accurate lappingcontact with the gauge. The parts being so assembled and adjusted, thelathe is started. Rotation of the face plate 1? drives the gauge, thelapping device normally rotating as a unit with the gauge on the centers1 and During such rotation, the

Transverscly extend. ing lapping teeth 9 formed in the outer suroperatorretards the rotation of the lapping device by placing his hand on thehand wheel 13. Continued rotation of the gauge, because of its threadedengagement with the lapping members 6, moves th'elapping memberslongitudinally therethrough along their guideways 5 from the positionshown in full lines in Fig. 2 to the position shown in dot and t ashlines. When the member 10 strikes the member a, all the parts, againrotate together as a unit. The operator now reverses the rotation of theface plate and, upon retarding the rotation of the lapping device, theparts are brought back to the position shown in full lines. Thus, thelapping operation is performed by reversing the rotation of the gaugeand moving the lapping members back and forth there through. It will beunderstood that, since the conical arrangement of the guidewayscorresponds to the taper of the gauge, the lapping members maintaintheir lapping relationship with the gauge during their longitudinalmovement therethrough.

hat I claim is: j

1. The method of lapping an internal taper gauge comprising supportingthe gauge on a plurality of relatively long lapping members supported ina conical relationship corresponding to the taper of the gauge andproviding a relative rotation and a relative longitudinal movementbetween the gauge and the said members While maintaining the membersintheir said relationship and in lapping contact with the gauge.

2. The method of lapping an internal taper gauge comprising supportingthe gauge on a plurality of relatively long lapping members supported ina conical relationship corresponding to the taper of the gauge andproviding a relative rotationand a relative longitudinal movementbetween the gauge and the said members while moving the members bodilyin a radial plane and holding the same in lapping contact with thegauge.

3. The method of lapping an internal taper gauge comprising supportingthe gauge on a plurality of relatively long lapping members supported ina conical relationship corresponding to the taper of the gauge andproviding a relative rotation and a relative longitudinal movementbetween the gauge and the said members while moving the members bodilyin a radial plane without changing their said relationship and holdingthe members in lapping contact with the gauge.

4. The method of lapping an internal taper thread gauge comprising thesupporting of the gauge on and in threaded contact with lapping teethformed on a plural ity of relativelylong lapping members supif d aconical relationsh p correspond ing to the taper arelative rotation and'a relative longitudiported of the gauge and providing nal movementbetween the gauge and the said members while maintaining the menu hersin their said relationship and the teeth thereof in threaded lappingcontact with the gauge. I I j i p 5. The method of lapping an internaltaper thread gauge comprisingthe support ing of the gauge on and inthreaded contact with lapping teeth formed on a plurality oi relativelylong lapping members supported in a conical relationshipcorresponding-to the taperof the gauge and providing a-relative rotationand a relative longitudinal movement between the gauge and the saidmembers while moving the members bodily in a radial plane and holdingthe teeth thereotin threaded lapping contact with the gauge.

6. The method of lapping an internal taper thread gauge comprising thesupportmg of the gauge on and'in threaded contact with lapping teethformed on a plurality of relatively long lapping members supin a conicalrelationship correspond ing to the taper of the gauge and providing arelative rotation and a relative longitudinal movement between the gaugeand the said members while moving the members bodily in a radial planewithout changing their said relationshipand holding the teeth thereof inthreaded lapping contact with the gauge.

7 The method of lapping an internal taper thread gauge comprising thesupporting of the gauge on and in threaded contact with lapping teethformed on a plural ity of relatively long lapping members supported in aconical relationship corresponding to the taper of the gauge androtating the gauge and moving the said members longitudinallytherethrough and in a radial direction bodily while maintaining themembers in their said relationship and the teeth thereof in threadedlapping contact with the gauge.

8. An internal taper thread gauge lapping device comprising thecombination of a plurality of relatively long lapping membershavingtransversely extending teeth adapted to engage the threads of thegauge to be lapped and means within and supporting such members in aconical relationship corresponding to the taper of the gauge to belapped, the members being free to slide longitudinally of the supportand the arrangement of the parts being such that as a relative rotationis effected between the gauge and the lapping members sncl'i-parts,because of theirthreaded engagement, also partake of a relativelongitudinal movement while the lapping members maintain their conicalrelationship and their threaded lapping engagement with the gauge.

, teeth adapted to'engage the threads "9. An internaltaper thread'gauge'lapping device'comprising the combination of I a'member having aplurality of conically arranged guideways therein and a plurality ofrelatively long 1 gauge lapping l members respectively mounted to slidein the guideways and having transversely extending gauge to be lapped,the members being free to slide longitudinally of the support and thearrangement of the parts being'such that as a relative rotationisetiected between the gauge and the lapping members such parts, becauseof their threadedenga ement, also partake of a relative longitudinalmovement and the lapping members move bodily in a radial direction whilemaintaining their conical relationship and their threaded lap pingengagement with the gauge.

l 10. An internal taper thread gauge lap ping device comprising thecombination of a member having aplurality of conically. arrangedguldeways therein,

a plurality of relatively [long gauge lapping members respectivelymounted to slide in the guide' ways and having transversely extendingteethadapted to engage the threads of the gauge to be lapped, and meansmovable relative to the-first named member and sup vporting one end ofeach of the lapping memhere, the members being free to slidelongitudinally or" the support and the arrange ment of the parts beingsuch that as a relative rotation is effected between the gauge and thelapping members such parts, because of their threaded engagement, alsopartake of a'relative longitudinal movement While the lapping membersmaintain their conical relationship and their threaded lappingengagement with the gauge.

11. An internal taper thread gauge lapin device com 'rism thecombination of supported thereon and an arbor, a member having aplurality of conically arranged guideways therein, a plurality ofrelatively long lapping members having transversely extending teethadapted to engage the threads of the gauge to be lapped and meansslidably mounted on the arbor and supporting one end of each of thelapping mem bers, the members being free to slide longitudinally of thesupport and the arrangement of the parts being such that as a relativerotation is eiiected between the gauge and the lapping members suchparts, be cause of their threaded engagement, also partake of a relativelongitudinal movement while the lapping members maintain their conicalrelationship and their threaded lapping engagement with the gauge.

of the 12; An internal taper thread gauge lapping device comprising thecombination of an arbor adapted to be rotatably supported on centers, amember supported on the arbor and having a plurality or conicallyarranged guideways therein, a plurality of 3 adapted to engage thethreads of the gauge to be lapped, means slidably mounted on the arborand supporting one end of each of the lapping members, and meansforretarding the rotation of the arbor, the members being free to slidelongitudinally of the support and the arrangement being such that as thegauge is rotated in one direction and the arbor held against rotationthe lapping members, because of theirthreaded engagement with the gauge,will move longitudi- 15 nally through the gauge in one direction andwill move longitudinally in the opposite direction when the gaugerotation 1s reversed, and the conical arrangement of the guidewayscorrespond to the taper 0t 20 In testimony whereof, I hereto aliix my 25signature.

EARLE BUCKINGHABL

